Cannot set frame format in avfoundation

[bookshiyi]

As mentioned before : https://github.com/l1npengtul/nokhwa/issues/72#issuecomment-1380531832

Even if I use function camera.set_frame_format(FrameFormat::YUYV) try to set frame format to YUYV, but frame's format is still NV12 by function camera.frame().unwrap().source_frame_format()

After some checks：

• https://github.com/l1npengtul/nokhwa/blob/dd0cd6e62850ba3a08de8d4fbd682b7033156459/src/backends/capture/avfoundation.rs#L207-L211

  • https://github.com/l1npengtul/nokhwa/blob/dd0cd6e62850ba3a08de8d4fbd682b7033156459/src/backends/capture/avfoundation.rs#L142-L146
  • https://github.com/l1npengtul/nokhwa/blob/dd0cd6e62850ba3a08de8d4fbd682b7033156459/nokhwa-bindings-macos/src/lib.rs#L972-L1029 problem may come from here(function set_all):

---

• set_frame_format()
  • set_camera_format()
  • set_all()
    • I think descriptor.frame_format may be handled here but I didn't find it.

Thanks to all contributors.

[bookshiyi]

btw, may an another bug in these code? https://github.com/l1npengtul/nokhwa/blob/dd0cd6e62850ba3a08de8d4fbd682b7033156459/nokhwa-bindings-macos/src/lib.rs#L1014-L1026

only min_frame_duration but max_frame_duration can not be found

[bookshiyi]

I found a temporary solution that may help people with similar problems:

Use camera.set_camera_requset(request) after camera.open_stream() to set frame_format to YUYV, it can work.

btw, If you want set frame format to YUYV by function set_frame_format() in anywhere, or set_camera_request() before open_stream(), maybe not take effect.

Although I don't know where the problem is.

[yamt]

related: https://github.com/l1npengtul/nokhwa/pull/151